Just look at Crescent Rose. Even if we forget the fact that the sharp end is pointing towards the user, the amount of intricate moving parts is ridiculous. Imagine trying to use that after a weeklong excursion through a Grimm-infested swampland with constant combat and little time for maintenance. Without anime physics holding it together it'd jam and break before the second day was over.

Coco's weapon is another one of questionable usability. With that kind of RPM she'd have to carry a metric fuckload of ammo to be useful. Small-caliber firearms like Blake's and Ren's are also a somewhat odd choice when the Grimm which keel over when shot by 9mm die to a backhanded Aura slap anyway. Deathstalkers et al which are the real threat don't give a fuck about Ruby's .50 rounds, so anything less might as well be rubber bullets. (Dis)honorable mentions go to Adam's weapon for being unable to shoot without removing the sword first, Blake for defeating the purpose of a sheath by sharpening it and stabbing herself in the eye with recoil, Nora for beating people with a magazine of high-explosives, Nolan for using a cattle prod and Flynt for weaponizing a fucking trumpet of all the things.

In the more practical end of the spectrum we have weapons like Myrtenaster and May's sniper. Revolvers in general are favored because they are extremely simple (and thus reliable) and handle large calibers well. Deseret Eagle, for example, is infamous for its misfeeds since huge cartridges can't be moved around that easily with just springs alone.
If you insist upon having a selectable array of magic plot juice cartridges built into your weapon, having it in a robust cylinder to house them in a rapier is a very reasonable way of doing it. The mechanism is very simple and almost impossible to mess up. The strength of May's weapon is also in its simplicity; it has barely any moving parts, and even if the axe blade happens to jam it doesn't really affect the performance of the weapon.

The tidbit that "humans only use 10% of their brains" is only very technically speaking true. All of the neurons aren't active at all times. It's not that we can't use 100%, that's just called a "seizure" and it's not a very productive state of mind.

It's like saying that only 0.5% of the roads are used. Technically speaking yes, only a tiny portion of the tarmac has a car on top, but what would be the point of having cars everywhere? They're not necessary and would just get in each other's way.

Think of 1D as a ruler. You just need the length to accurately tell where a point on a ruler is. A map, conversely, needs both longitude and latitude. In 3D you also need the height, and finally in the real world you need to know "when" to accurately describe a point in spacetime.

When submitting art, including the name makes searching for old posts significantly easier, as reddit's search function is very rigid and usually fails to find content without specific keywords to look for. You are free to resubmit with a rephrased title.

Reddit changed how they display the votes. Before, to confuse voting bots (and a lot of users as a side effect) reddit fuzzed the vote numbers which normalized most popular posts closer to 50-50 up/downvote ratio and rarely over 10k positive votes. The numbers still aren't accurate, but they're not as grossly manipulated anymore.